Ursula Le Guin’s novels The Left Hand of Darkness (1969) and The Dispossessed (1974) rely upon the description of fantasy worlds whose organizing systems were initially a reflection of the need to create the perfect society. From this perspective, both the lack of gender distinctions on the planet Gethen/Winter in the former novel and the abolition of social inequality on the planet Anarres in the latter novel represent failed experiments of the attempt to transform a dream-like world into reality. This paper aims at identifying the guiding principles of the alien communities in the two science-fiction novels and the reasons …